1. Field of the Invention
This invention relates generally to roof coverings and more particularly to a roofing panel providing an integral ridge cap and a stiffening step designed to cover the ridge cap in an overlapping panel arrangement.
2. Description of Related Art
The following art defines the present state of this field:
Guffey et al., U.S. Pat. No. 5,295,338 describes a panel assembly for buildings and the like comprising, in combination with structure supporting the assembly, an array of overlapping elongated metal panels, each panel including a lower edge, an upper flange, and a web including at least one outwardly protruding longitudinally extending stiffening rib. The stiffening rib adjacent the upper flange has an elongated longitudinally extending groove and an extended bearing portion for contacting the structure when the panel is fastened thereto. These ribs provide structural support without purlins, sheathing, or the like. A plurality of fasteners for attaching the panel assembly to the structure pierce the extended bearing portion hold the bearing portion in contact with the structure so that when panels are affixed to the structure with the lower edge of one panel overlapping the upper flange of another panel, the groove forms a space between overlapping panels to prevent water from flowing around the stiffening rib adjacent the upper flange.
Pittman et al., U.S. Pat. No. 4,580,383 describes a building panel for exterior and interior wall and roof surfaces comprises an elongated body formed of relatively thin, molded hardboard having upper and lower edges, opposite ends, and outer face adapted for exposure to the weather and a back face generally following the contour thereof. The body includes a lower edge portion extending upwardly and outwardly of the lower edge of the panel and integralling joining and intermediate fascia portion spaced outwardly of the lower edge. An upper edge portion integrally joins an upper edge of the intermediate fascia portion and includes an upwardly and outwardly extending segment adapted to underlie a lower edge portion of a panel(s) laid up in a next higher course. The upper edge portion also includes a second segment extending between the first segment is generally parallel of the intermediate fascia panel portion and is adapted to underlie a portion of intermediate fascia portion of a panel(s) laid up in a next higher course. The upper edge portion is formed with a plurality of longitudinally spaced apart fastener receiving depressions extending inwardly of an outer face of the second segment of the upper edge portion. Longitudinally extending slot means are cut through the thin molded hardboard in the depressions between the inner and outer faces for receiving the shank of a nail or other fastener for securing the panels in place.
Bisson, U.S. Pat. No. 4,736,565 describes wall siding panels having vertical edge portions adapted to overlap and fasteners preventing the vertical joins so formed from bending or bulging outwardly. The panels have declinations and flat lengthwise, horizontal shoulders joining the declinations to resemble clapboard finishing. A female aperture is formed in each shoulder of one panel adjacent its vertical edge portion and a male projection is formed in each shoulder of the other panel adjacent its vertical edge portion. When a pair of two longitudinally-spaced, oppositely-directed projections are provided, which are selectively used so as to permit panel overlapping in any order edge portions are overlapped, each projection elements have identical profiles.
Heckelsberg, U.S. Pat. No. 33,566 describes a roof structure and its components comprises a series of metal panels having flanges that interlock when the panels are laid side by side and which are subsequently tightly seamed together to convert the individual panels into an integrated roof forming membrane. The roof structure may be insulated through the use of a blanket vapor barrier and insulation under the panels preferably along with thermal blocks located over the purlins. The roof structure includes unique flexible panel mounting clips that attach the panels to the purlins in such a way as to permit the panels to expand or contract in response to temperature and pressure changes, thereby minimizing roof stressing.
Heckelsberg, U.S. Pat. No. 4,224,775 describes the primary components of a roof structure which comprising a series of substantially identical metal panels having flanges that interlock when the panels are laid side by side and which are subsequently tightly seamed together to convert the individual panels into an integrated roof forming membrane. The interlock joints between adjacent panels are adapted for connection to flexible panel mounting clips that attach the panels to the purlins in such a way as to permit the panels to expand or contract in response to temperature and pressure changes, thereby minimizing roof stressing.
The prior art teaches the fabrication and use of building panels of various materials including metal sheets and constructions using such panels wherein the panels overlap and interlock at, or near their edges. However, the prior art does not teach that a roof panel having longitudinally ribs may be constructed and shaped for elimination of a ridge cap and for covering a convex coving portion with a step portion of an abutting panel laid overlapping and atop. The present invention fulfills these needs and provides further related advantages as described in the following summary.